The present invention is directed to an improved breathable compressive sleeve or device constructed to convey moisture away from the skin so as to deter irritation. More particularly, it is concerned with a device of laminate multilayer construction including a hygroscopic polymeric film layer such as hydrophilic polyurethane foam for the purpose of drawing moisture from the surface of the skin and deterring the collection of moisture between the underlying skin and the device by drawing the moisture into the interior of the sleeve and toward the exterior of the device opposite the skin. The preferred sleeve construction is freely stretchable to conform to the muscles and joints of a user and provides a moisture attractant whereby moisture is pulled away from the underlying skin thus providing dry, slip-resistant compression and in certain applications support without impairing breathability of the device. The construction of the device may be utilized for compression in the form of sleeves or other compressible structures for various types of moisture management, wound care, lymphedema care and for other purposes having similar requirements.
The upright posture of the human body renders it particularly susceptible to strains, sprains and other injuries which are generally manifested by swelling, inflammation and discomfort. In addition, bed sores and the like also sometimes require compression and/or moisture management. When severe, an injury may result in impaired mobility and necessitate restriction of movement and activity or the patient may be impaired due to age or infirmity. The body is also subject to formation of fibrin clots which may obstruct vessels in the peripheral circulation when the body is in the prone position for prolonged periods. In addition to localized morbidity, such clots may also break free and travel to the heart or lungs causing more serious damage.
Orthopedic injuries have economic as well as physical repercussions for professional athletes engaged in competitive sports. Sidelined athletes lose not only the opportunity to perform, but experience a reduction in their overall level of fitness during periods of restricted activity, necessitating a period of retraining prior to resumption of competition. Of course, most individuals are not professional athletes and they engage in less strenuous activities such as jogging, calisthenics, walking and occasional competitive sports.
However, non professional athletes also experience discomfort when injured and their level of physical fitness is also impaired by injury-enforced inactivity. Moreover, amateur athletes may be more susceptible to injury, since they generally lack the advice of professional trainers as well as the fitness and judgment developed by professional athletes. Those who engage in infrequent bouts of strenuous exercise without training are most at risk of injury. However, even the well-trained amateur athlete is subject to occasional strains and sprains. Some individuals are particularly at risk of injury because of previous traumatic injury which has left continuing weakness in a joint or limb. Other individuals are at greater risk because of their advanced age or general state of health and fitness.
The importance of providing compressive support to limbs and joints which have been injured or weakened or which are subject to stress, such as may be caused by strenuous exercise, is well recognized. So-called R.I.C.E. therapy (rest, ice, compression, elevation) is commonly recommended for implementation following minor athletic injuries. Such therapy is known to be particularly effective when cold and compression are applied immediately following an injury and the compression is continued for a period of about 24 to 48 hours. The need to provide compression to facilitate venous return in bed bound patients in order to prevent formation of blood clots is similarly well recognized. It is also well known that certain wounds, wherein there are open sores or the like, respond well to compression.
Orthopedic compression bandages, braces and sleeves have long been employed to provide support for athletic and medical purposes. They are commonly worn over the wrists, elbows, knees and ankles. They are also frequently employed on the lower legs and forearms, and, less frequently, on the upper legs and arms, shoulders and chest. They provide support during normal movement, which support may be especially required by persons recovering from previous injuries or by persons who are frail or elderly. Such compression devices also provide support for ligaments, tendons, muscles and joints against the stresses of over extension which may occur during exercise. In this manner, they help to prevent orthopedic and muscular injury or reinjury or enhance wound healing or treatment. Elastomeric sleeves have also been employed, commonly in the form of stockings, to provide compression in order to facilitate peripheral venous return from the legs of bed bound patients, thereby helping to prevent embolism.
Such compression support devices are often of elastomeric construction, either in the form of sleeves, dressings or strips which may be slipped over or wound around the affected area and fastened by means of hook and loop fasteners or specialized clips or pins. Devices made in accordance with the present invention may also be used for wound care with compression or without compression where compression is not required, but where moisture management is desired, or for other purposes where moisture control next to the skin is desired.
A number of materials have been employed in the construction of such support devices. Dressing, strip and sleeve-type supports are generally constructed of knitted or woven stretchable webbing such as cotton-wound threads or synthetic resin compositions such as neoprene. Laminate multilayer composite materials have recently become available which are thinner than previously used woven material and especially neoprene. Such multilayer materials may be fabricated into sleeve or bandage-type supports and treatment devices. Multiple layer devices are often five layers thick, with a synthetic resinous film layer sandwiched between two adhesive layers, each of which is covered by an outer layer of a synthetic fabric such as nylon. In such prior art devices, the resinous film layer has been hydrophobic with respect to liquid moisture, but breathable. That is, films of this type allow passage of gas vapors, including water vapor to some extent, but generally block passage of liquid water. Therefore, because moisture produced at the skin level seldom can completely evaporate when covered, the synthetic hydrophobic resinous film layers of the prior art form an impermeable liquid moisture barrier to some degree which traps moisture against the skin within the structure.
Braces have been constructed of multiple layers. The various layers each have a purpose such as to provide protection from the cold, to provide a surface that is susceptible to cleaning or to provide a non-slip surface with a high coefficient of friction against the skin to reduce migration of the brace.
Multiple layer or single layer supports constructed of neoprene generally do not permit the underlying skin of the wearer to breathe well and trap moisture between the support and the skin. In active persons, especially athletes or persons exercising or where a wound is seeping fluid, the support or other device often beneficially traps and holds heat to aid some problems; however, the heat causes additional sweating and produces more moisture that in turn is trapped by such prior art devices against the skin. Because such impermeable supports lack the ability to carry away moisture, extended or frequent wear may be uncomfortable as well as irritating to the skin. If such irritation is prolonged, it can result in morbidity such as dermatitis and sloughing of the skin or failure of a wound to head properly. Such impermeable materials are especially unsuitable for compression bandages to be worn by amputees or individuals with impaired circulation, who may develop necroses. In addition, since impermeable supports provide no outlet for perspiration excreted by the wearer, a salt residue may be deposited on the inner surface of the support which eventually may shorten the effective life span of the support and adds to irritation of the skin.
None of the previously available materials and combinations of materials provide effective compression and/or support while providing for the removability of moisture from contact with the underlying skin surface and providing an effective system for conveying liquid moisture away from the skin. Accordingly, there is a need for various devices to convey moisture from the skin and, in particular, for a compression support sleeve for athletic and medical uses which is light weight, comfortable, stretchable to conform to the anatomy of a user and to permit moisture management and tissue movement, which enhances transport breathability of the underlying skin or circulation of the underlying blood vessels and which reduces moisture in contact with the skin by conveying moisture away from the skin to the outer surface of the support rather than trapping it between the skin and the support.
Furthermore, many worldwide national governments have determined that devices that promote retention of moisture on the surface of the skin are potentially harmful for certain uses and have passed or may soon pass legislation that favors devices for such uses that promote removal of moisture from the skin, thereby increasing the demand for devices of the type found in the present application.